Distributivity, a versus some, and groups versus plurals

[nyzoe]

Dear native speakers of English, once again I’d like to call on your invaluable help with some pesky semantic stuff :)

First a test question: in your variety of English, can you use (a) in a situation where each individual team member is wearing their own shirt?
(a) The team members are wearing an orange shirt with blue stripes.
If you can’t (i.e. if you can only get this interpretation with a plural ‘orange shirts’) - please skip question 1 :)

Question 1:
If you can get the so-called ‘distributive’ interpretation for (a), what about the similar
(b) The team members are wearing some orange shirt with blue stripes.
Does this have an interpretation where each individual team member is wearing their own shirt? Is it as readily available as with (a), or is it more difficult or even impossible to get?

Question 2:
Imagine we have some singers and dancers divided into two teams. Of Team A, half of the members is dancing, the other half is singing. Of Team B, all members are dancing. I’m assuming that (c) is completely unproblematic in this situation…
(c) The members of Team A are dancing or singing. (The members of Team B are only dancing.)
…but what about (d)? Does it mean the same, or can I only use it in a situation in which all members of team A are doing the same thing (either dancing or singing)?
(d) Team A is dancing or singing. (Team B is only dancing.)

Thanks! :)